Having already spent around $3 billion on its DePuy Orthopaedics ASR hip implant recall, Johnson & Johnson is facing another potential debacle involving a metal-on-metal version of its Pinnacle Hip Replacement System. According to a report from Reuters, Johnson & Johnson and its DePuy unit already face some 1,600 metal-on-metal hip implant lawsuits over its Pinnacle device, all of which allege the implant caused metallosis and other injuries similar to those seen with the recalled ASR hip replacement devices.

Doctors who are tracking large groups of DePuy hip implants patients estimate that more than 10% of the metal-on-metal Pinnacle hips will have failed in the next two to three years, Reuters said. As we’ve reported previously, the DePuy ASR hip replacement devices were recalled in August 2012 after they were found to be failing in about 12 percent of patients within just five years of implantation.

Problems reported by patients with failing DePuy Pinnacle hip implants are identical to those experienced by ASR hip replacement victims. In addition to pain, swelling, and dislocation, doctors are seeing all-metal Pinnacle hip implant patients with high levels of metal ions in their blood. This can result in metallosis, a reaction that results in tissue and bone loss, the formation of pseudotumors, and long-term heart, kidney, nerve and thyroid problems, Reuters said.

Since the DePuy ASR hip implant recall, the entire class of metal-on-metal hip implants has come under scrutiny, as a number of studies have found evidence that that the devices can shed dangerous amounts of chromium and cobalt into patients’ bloodstreams. Last month, the U.S. Food & Drug Administration (FDA) revealed that it had received 16,800 negative event reports involving metal hips between 2000 and 2011. Of those, more than 14,000 involved revision surgeries, in which a defective implant was removed. Recently, FDA’s Orthopaedic and Rehabilitation Devices Panel recommended that metal-on-metal hip implant patients undergo regular monitoring to ensure their devices are not failing. The panel also called for new warning labels for all-metal hip implants, including warnings regarding their association with the development of pseudotumors and high levels of metal ions in patients’ blood.

According to Reuters, many doctors believe Johnson & Johnson’s problems with metal-on-metal hip implants won’t end with the DePuy ASR hip implant recall. If that’s true, the all-metal Pinnacle device could turn out to be a much larger headache for the company compared to the ASR debacle. According to Reuters, only around 37,000 patients in the U.S. received an ASR hip implant device. But some 150,000 have been fitted with a metal-on-metal Pinnacle implant. Should plaintiffs be successful in their Pinnacle lawsuits, Johnson & Johnson could end up paying nearly $5 billion just to cover patients’ revisions surgeries, Reuters said.

While Johnson & Johnson is covering medical costs for people who have failing ASR devices, it has denied that there are any problems with the Pinnacle. According to Reuters, patients with failing Pinnacle implants have not received any help from the company. Johnson & Johnson is also taking a much harder line in defending itself against Pinnacle hip implant lawsuits, compared to its approach to the ASR hip replacement litigation.

According to Reuters, it’s been difficult to come up with hard numbers for the rate of all-metal Pinnacle failures. DePuy puts the failure rate at about 4 to 4.5 percent. But a plaintiffs’ attorney involved in the Pinnacle litigation told Reuters that problems with the Pinnacle are being reported less systematically compared to the ASR hip implants, since the Pinnacle devices weren’t recalled. According to Dr David Langton, an orthopedist in the U.K. who has been tracking a group of about 1,000 metal-on-metal Pinnacle recipients, the device has a failure rate of 8 percent at five years, and 16 percent after 6-1/2 years. Langton believes it’s only a matter of time before Pinnacle failure rates climb. And while the failure rate may never equal what’s been seen with the ASR hip implants percentage-wise, the total number of patients affected could be far greater, Reuters said.